How TCP Handles Errors And Uses Windows | Network Fundamentals Part 9 TCP doesn’t detect errors; That’s layer-2’s job. But it does notice when data is missing, and it is able to retransmit segments as needed. It does this by using the ACK flag in the TCP header. The ACK flag acknowledges when segments arrive correctly. To improve efficiency, a range of segments can be acknowledged at once. The amount of data that can be acknowledged at a single time is called the window size. When a network link is stable, the window size can increase, allowing more data to be sent per acknowledgement. If the link is unstable, the window size shrinks, which lowers the number of retransmissions. Windowing is TCP’s flow control. The answers to the quiz questions, a must for CCENT and CCNA candidates, can be found at: https://networkdirection.net/labsandquizzes/quizzes/error-recovery-and-flow-control-quiz/ The CCENT/CCNA study guide (affiliate): https://click.linksynergy.com/link?id=RL4E*8CmbSY&offerid=145238.2445867&type=2&murl=http%3A%2F%2Fwww.ciscopress.com%2Ftitle%2F9781587205804 In the next video, we’re finally going to see the first steps in configuring a router or switch. Overview of this video: 0:00 Introduction 0:19 Data Loss 0:50 Acknowledgements 2:52 Windowing 4:27 Quiz #1-2 4:44 Error Recovery 6:05 Dynamic Windows 8:51 Quiz #3-4 LET'S CONNECT 🌏 null 🌏 https://twitter.com/NetwrkDirection 🌏 https://www.patreon.com/NetworkDirection 🌏 https://www.networkdirection.net/